Supplementary Material for: Modelling the Long-Term Health Outcome and Costs of Thrombectomy in Treating Stroke Patients with Large Ischaemic Core: Comparison between Clinical Trials and Real-World Data

Introduction: We aimed to assess the long-term health outcomes and costs of endovascular thrombectomy (EVT) using clinical trials and real-world evidence in patients with large ischaemic core. Methods: Both clinical trials and the INternational Stroke Perfusion Imaging REgistry (INSPIRE) were used. Patients with acute computed tomography perfusion scan with an ischaemic core of ≥70 mL were included. A Markov model was constructed to simulate the long-term costs and health outcomes (quality-adjusted life year) post-index stroke. Effectiveness of EVT (modified Rankin scale score at 3 months) was derived from the trials and INSPIRE registry (compared to matched patients not treated with EVT), respectively. Results: Based on the trial and real-world data, the overall results revealed varied health benefits and costs due to EVT, with reduced health benefits and increased costs from EVT treatment in everyday practice. The long-term simulation estimated that offering EVT to large vessel occlusion stroke patients with large ischaemic core was associated with greater benefits (1.12 vs. 0.25 quality-adjusted life year gains) and lower (−A$19,320) or higher costs (A$11,278), using trial and real-world data, respectively. The incremental cost of the EVT procedure (i.e., A$14,356) could be primarily offset to a different extent by the reduction in costs related to the nursing home care (−$31,986 vs. −A$1,874) in the clinical trial and real-world practice. Conclusions: Our results highlight the potential gaps when implementing an effective intervention in the real world and the importance of the rigorous selection of large infarct core patients for EVT